Communication apparatus and communication method

ABSTRACT

A mobile communication system in which a mobile station apparatus transmits reception quality information to a base station apparatus, the reception quality information indicating quality of a signal received from the base station apparatus, characterized in that the base station apparatus transmits information for instructing transmission of reception quality information without uplink data included in an uplink data transmission permission signal, and the mobile station apparatus transmits reception quality information without uplink data according to the information for instructing transmission of reception quality information without uplink data. This allows a mobile station apparatus to transmit reception quality information including a large amount of information even if there is no uplink data between the mobile station apparatus and the base station apparatus, and the transmission control flexibly responding to the amount of information and the frequency of transmissions of the reception quality information transmitted from the mobile station apparatus is possible. Therefore, more efficient communication control (scheduling) between the base station apparatus and the mobile station apparatus can be achieved.

TECHNICAL FIELD

The present invention relates to a communication technique, andparticularly, to a mobile communication system in which a mobile stationapparatus measures reception quality of a signal received from a basestation apparatus to transmit reception quality information to the basestation apparatuses, and relates to a base station apparatus and amobile station apparatus which are adapted to the mobile communicationsystem.

BACKGROUND ART

Recently, demand for data communication is increasing in a mobilecommunication system, and various techniques are proposed to obtain highfrequency use efficiency meeting the increase in the communication dataassociated with the demand. One of the techniques for increasing thefrequency use efficiency is OFDMA (Orthogonal Frequency DivisionMultiple Access). The OFDMA relates to a technique of modulation methodof communication in which the same frequency is used in all cells in acommunication area constituted by the cells, and the OFDMA can achievefast data communication. In the scheduling of transmission packets inthe OFDMA system, a method is known in which mobile station apparatusestransmit CQI (Channel Quality Indicator), which is informationindicating the reception quality of a downlink state for sub-carriers inwideband, to a base station apparatus, and the base station apparatusperforms scheduling of the packets based on the CQI of sub-carriers inwideband transmitted from the mobile station apparatuses.

Furthermore, in the scheduling of transmission packets in an OFDM(Orthogonal Frequency Division Multiplexing) system using a plurality ofsub-carriers, a technique is also known in which mobile stationapparatuses evaluate each channel states of a downlink (frequencycharacteristics, or characteristics such as transmission loss dependenton the frequency) and transmit information with quantized each channelstates to a base station apparatus, and the base station apparatusdetermines sub-carriers to be assigned to the mobile station apparatusesbased on the transmitted information (see, Patent Document 1 below).FIG. 5 is a diagram showing an overview of a conventional communicationmethod between a base station apparatus and a mobile station apparatus.FIG. 5(A) is a diagram showing a system configuration example, and FIG.5(B) is a diagram showing a characteristic example. Having receiveddownlink information 205 of a downlink line used for reception qualitymeasurement from a base station apparatus 201, a mobile stationapparatus measures the reception quality of each channel (FIG. 5(B))based on the downlink information and quantizes the measured receptionquality of each channel to create a channel profile of a propagationpath.

The channel profile created by the mobile station apparatus 203 istransmitted, from the mobile station apparatus 203 to the base stationapparatus 201, as reception quality information 207 using an uplinkline. The base station apparatus 201 executes processing, such asadaptive modulation and coding or frequency selective scheduling, uponsignals transmitted from the base station apparatus 201 to the mobilestation apparatus 203 based on the reception quality information 207.

In relation to the transmission of reception quality information by themobile station apparatus to the base station apparatus, transmissionfrom the mobile station apparatus to the base station apparatus by usinga dedicated uplink control channel (hereinafter, referred to as PUCCH(Physical Uplink Control Channel)) and an uplink shared data channel(hereinafter, PUSCH (Physical Uplink Shared Channel)) is examined in theevolution of third generation wireless access (Evolved UniversalTerrestrial Radio Access) examined in 3GPP (3rd Generation PartnershipProject) that is an international standardization project. For example,Non-Patent Document 1 described below proposes transmitting thereception quality information using the PUCCH or the PUSCH depending onthe type of services, in which required reception quality informationvaries, when the mobile station apparatus transmits the receptionquality information to the base station apparatus.

Patent Document 1: JP Patent Publication (Kokai) No. 2005-130491A

Non-Patent Document 1: “CQI handling during DRX”, 3GPP, TSG RAN WG2Meeting #58, R2-071901, May 2007

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

However, in the above conventional technique, uplink data and receptionquality information needed to be transmitted at the same time when themobile station apparatus transmits the reception quality informationusing the PUSCH. Thus, there was a problem that the mobile stationapparatus could not transmit the reception quality information using thePUSCH if there was no uplink data to be transmitted to the base stationapparatus. In general, since the resource region assigned as the PUCCHis smaller than the resource region assigned as the PUSCH, the amount ofinformation of the reception quality information that can be transmittedusing the PUCCH is small. On the other hand, the reception qualityinformation transmitted using the PUSCH is reception quality informationincluding a large amount of information.

The base station apparatus performs processing, such as adaptivemodulation and coding or frequency selective scheduling, upon thesignals to be transmitted to the mobile station apparatus based on thereception quality information transmitted from the mobile stationapparatus. When the mobile station apparatus transmits reception qualityinformation including a small amount of information using the PUCCH, thebase station apparatus does not execute processing, such as highlyaccurate adaptive modulation and coding or frequency selectivescheduling, in accordance with the amount of information, or executesonly the processing of adaptive modulation and coding to transmitsignals to the mobile station apparatus. When the mobile stationapparatus transmits reception quality information including a largeamount of information using the PUSCH, the base station apparatusexecutes processing, such as highly accurate adaptive modulation andcoding or frequency selective scheduling, based on the information totransmit signals to the mobile station apparatus.

In this way, when the reception quality information transmitted from themobile station apparatus includes a large amount of information, thebase station apparatus can perform processing, such as highly accurateadaptive modulation and coding or frequency selective scheduling, uponthe signals to be transmitted. As a result, the communication control(scheduling) between the base station apparatus and the mobile stationapparatus can be more efficiently performed.

There are various types of services performed between the mobile stationapparatus and the base station apparatus, such as VoIP (voice call), WEBbrowsing, and TV phone. One of the services is a service of continuingto download a large amount of data (UDP packets) such as moving images,and in that case, there is no uplink data to be transmitted from themobile station apparatus to the base station apparatus.

Thus, in the conventional technique, the mobile station apparatus cannottransmit the reception quality information including a large amount ofinformation using the PUSCH in a service in which a great amount of data(UDP packets), such as moving images, is continuously downloaded withoutthe uplink data. This means that the base station apparatus cannotperform processing, such as highly accurate adaptive modulation andcoding or frequency selective scheduling, upon the signals to betransmitted in the case of services without the uplink data, and thatthe communication control (scheduling) between the base stationapparatus and the mobile station apparatus cannot be more efficientlyperformed.

Furthermore, in the conventional technique, there was no specificdescription of what kind of control information the base stationapparatus uses to control the mobile station apparatus when the mobilestation apparatus transmits only the reception quality information usingthe PUSCH, and what kind of exchange is made between the base stationapparatus and the mobile station apparatus to transmit the receptionquality information. In the transmission of the reception qualityinformation by the mobile station apparatus to the base stationapparatus, there is a demand that the base station apparatus controlsthe amount of information and the frequency of transmissions of thereception quality information transmitted from the mobile stationapparatus. The base station apparatus should control the amount ofinformation and the frequency of transmissions of the transmittedreception quality information in consideration of the uplink resource inthe cell controlled by the base station apparatus. If large-sizedreception quality information is frequently transmitted based on thedecision of each mobile station apparatus, the uplink source in the cellbecomes scarce, and if small-sized reception quality information istransmitted infrequently, the uplink resource is wasted. Thus, when themobile station apparatus transmits the reception quality information tothe base station apparatus, what kind of control information the basestation apparatus uses to control the mobile station apparatus and whatkind of exchange is made between the base station apparatus and themobile station apparatus to transmit the reception quality informationare important issues. An efficient transmission control method is neededin which the amount of information and the frequency of transmissions ofthe reception quality information to be transmitted are taken intoaccount.

The present invention has been made in view of the foregoingcircumstances, and an object of the present invention is to provide amobile communication system, a base station apparatus, and a mobilestation apparatus which can transmit reception quality informationincluding a large amount of information from a mobile station apparatuseven if there is no uplink data between the mobile station apparatus andthe base station apparatus, and perform transmission control flexiblyresponding to the amount of information and the frequency oftransmissions of the reception quality information transmitted from themobile station apparatus to achieve more efficient communication control(scheduling) between the base station apparatus and the mobile stationapparatus.

Means for Solving the Problems

(1) The present invention provides a mobile communication system inwhich a mobile station apparatus transmits reception quality informationto a base station apparatus, the reception quality informationindicating quality of a signal received from the base station apparatus,characterized in that the base station apparatus transmits informationfor instructing transmission of reception quality information withoutuplink data included in an uplink data transmission permission signal,and the mobile station apparatus transmits reception quality informationwithout uplink data according to the information for instructingtransmission of reception quality information without uplink data.

(2) The mobile communication system is characterized in that the mobilestation apparatus transmits, to the base station apparatus, thereception quality information using an uplink shared data channel.

(3) The present invention provides a mobile communication system inwhich a mobile station apparatus transmits reception quality informationto a base station apparatus using an uplink shared channel, thereception quality information indicating quality of a signal receivedfrom the base station apparatus, characterized in that the base stationapparatus transmits information for instructing transmission ofreception quality information without uplink data included in an uplinkdata transmission permission signal, and the mobile station apparatustransmits reception quality information without uplink data according tothe information for instructing transmission of reception qualityinformation without uplink data.

(4) The present invention provides a mobile communication system inwhich a mobile station apparatus transmits reception quality informationto a base station apparatus, the reception quality informationindicating quality of a signal received from the base station apparatus,characterized in that the base station apparatus transmits informationfor instructing transmission of reception quality information withoutuplink data included in an uplink data transmission permission signal,the mobile station apparatus transmits reception quality informationwithout uplink data according to the information for instructingtransmission of reception quality information without uplink data; andat this time; and at this time, in case that ACK or NACK for downlinkdata needs to be transmitted, transmits reception quality informationand ACK or NACK without uplink data.

(5) The mobile communication system is characterized in that the mobilestation apparatus transmit, to the base station apparatus, the receptionquality information and the ACK or the NACK using an uplink shared datachannel.

(6) The present invention provides a mobile communication system inwhich a mobile station apparatus transmits reception quality informationto a base station apparatus using an uplink shared channel, thereception quality information indicating quality of a signal receivedfrom the base station apparatus, characterized in that the base stationapparatus transmits information for instructing transmission ofreception quality information without uplink data included in an uplinkdata transmission permission signal, the mobile station apparatustransmits reception quality information without uplink data according tothe information for instructing transmission of reception qualityinformation without uplink data; and at this time, in case that ACK orNACK for downlink data needs to be transmitted, transmits, to the basestation apparatus, reception quality information and ACK or NACK withoutuplink data.

(7) The mobile communication system is characterized in that theinformation for indicating transmission of reception quality informationwithout uplink data is represented by using information for instructingtransmission of reception quality information and informationconstituting an uplink data transmission permission signal.

(8) The mobile communication system is characterized in that theinformation constituting the uplink data transmission permission signalis HARQ redundancy version information.

(9) The mobile communication system is characterized in that theinformation constituting the uplink data transmission permission signalis MCS information.

(10) The mobile communication system is characterized in that theinformation constituting the uplink data transmission permission signalis transport block size information.

(11) The present invention provides a base station apparatus in a mobilecommunication system in which a mobile station apparatus transmitsreception quality information to the base station apparatus, thereception quality information indicating quality of a signal receivedfrom the base station apparatus, the base station apparatuscharacterized by comprising: means for transmitting information forinstructing transmission of reception quality information without uplinkdata included in an uplink data transmission permission signal to themobile station apparatus.

(12) The present invention provides a base station apparatus in a mobilecommunication system in which a mobile station apparatus transmitsreception quality information to the base station apparatus using anuplink shared channel, the reception quality information indicatingquality of a signal received from the base station apparatus, the basestation apparatus characterized by comprising: means for transmittinginformation for instructing transmission of reception qualityinformation without uplink data included in an uplink data transmissionpermission signal to the mobile station apparatus.

(13) The base station apparatus is characterized in that the informationfor instructing transmission of reception quality information withoutuplink data is represented by using information for information forinstructing transmission of reception quality information without uplinkdata transmission of reception quality information and informationconstituting an uplink data transmission permission signal.

(14) The base station apparatus is characterized in that the informationconstituting the uplink data transmission permission signal is HARQredundancy version information.

(15) The base station apparatus is characterized in that the informationconstituting the uplink data transmission permission signal is MCSinformation.

(16) The base station apparatus is characterized in that the informationconstituting the uplink data transmission permission signal is transportblock size information.

(17) The present invention provides a mobile station apparatus in amobile communication system a mobile station apparatus in a mobilecommunication system in which the mobile station apparatus transmitsreception quality information to a base station apparatus, the receptionquality information indicating quality of a signal received from thebase station apparatus, the mobile station apparatus characterized bycomprising: means for receiving an uplink data transmission permissionsignal including information for instructing transmission of receptionquality information without uplink data from the base station apparatus;and means for transmitting reception quality information without uplinkdata to the base station apparatus according to the information forinstructing transmission of reception quality information without uplinkdata.

(18) The mobile station apparatus is characterized in that the means fortransmitting reception quality information to the base station apparatustransmits the reception quality information using an uplink shared datachannel.

(19) The present invention provides a mobile station apparatus in amobile communication system in which the mobile station apparatustransmits reception quality information to a base station apparatususing an uplink shared channel, the reception quality informationindicating quality of a signal received from the base station apparatus,the mobile station apparatus characterized by comprising: means forreceiving an uplink data transmission permission signal includinginformation for instructing transmission of reception qualityinformation without uplink data from the base station apparatus; andmeans for transmitting reception quality information without uplink dataaccording to the information for instructing transmission of receptionquality information without uplink data to the base station apparatus.

(20) The present invention provides a mobile station apparatus in amobile communication system in which the mobile station apparatustransmits reception quality information to a base station apparatus, thereception quality information indicating quality of a signal receivedfrom the base station apparatus, the mobile station apparatuscharacterized by comprising: means for receiving an uplink datatransmission permission signal including information for instructingtransmission of reception quality information without uplink data fromthe base station apparatus; and means for transmitting reception qualityinformation without uplink data according to the information forinstructing transmission of reception quality information without uplinkdata to the base station apparatus, wherein in case that ACK or NACK fordownlink data needs to be transmitted when transmitting receptionquality information without uplink data according to the information forinstructing transmission of reception quality information without uplinkdata, the means for transmitting the reception quality information tothe base station apparatus transmits the reception quality informationand the ACK or the NACK without uplink data.

(21) The mobile station apparatus is characterized in that the means fortransmitting the reception quality information to the base stationapparatus transmits, to the base station apparatus, the receptionquality information and the ACK or the NACK using an uplink shared datachannel.

(22) The present invention provides a mobile station apparatus in amobile communication system in which the mobile station apparatustransmits reception quality information to a base station apparatususing an uplink shared channel, the reception quality informationindicating quality of a signal received from the base station apparatus,the mobile station apparatus characterized by comprising: means forreceiving an uplink data transmission permission signal includinginformation for instructing transmission of reception qualityinformation without uplink data from the base station apparatus; andmeans for transmitting reception quality information without uplink dataaccording to the information for instructing transmission of receptionquality information without uplink data to the base station apparatus,wherein in case that ACK or NACK for downlink data needs to betransmitted when transmitting reception quality information withoutuplink data according to the information for instructing transmission ofreception quality information without uplink data, the means fortransmitting the reception quality information to the base stationapparatus transmits reception quality information and ACK or the NACKwithout uplink data.

(23) The mobile station apparatus is characterized in that theinformation for instructing transmission of reception qualityinformation without uplink data is represented by using information forinstructing transmission of reception quality information andinformation constituting an uplink data transmission permission signal.

(24) The mobile station apparatus is characterized in that theinformation constituting the uplink data transmission permission signalis HARQ redundancy version information.

(25) The mobile station apparatus is characterized in that theinformation constituting the uplink data transmission permission signalis MCS information.

(26) The mobile station apparatus is characterized in that theinformation constituting the uplink data transmission permission signalis transport block size information.

ADVANTAGES OF THE INVENTION

According to the present invention, a mobile station apparatus cantransmit reception quality information including a large amount ofinformation even if there is no uplink data between the mobile stationapparatus and a base station apparatus, and the transmission controlflexibly responding to the amount of information and the frequency oftransmissions of the reception quality information transmitted from themobile station apparatus is possible. Therefore, more efficientcommunication control (scheduling) between the base station apparatusand the mobile station apparatus can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram showing a configuration of a basestation apparatus according to a first embodiment of the presentinvention.

FIG. 2 is a schematic block diagram showing a configuration of a mobilestation apparatus according to the first embodiment of the presentinvention.

FIG. 3 is a diagram for explaining a processing flow of a modifiedexample of the first embodiment of the present invention.

FIG. 4 is a diagram for explaining a second embodiment of the presentinvention and a processing flow.

FIG. 5 is a diagram for explaining a general communication method of abase station apparatus and a mobile station apparatus.

DESCRIPTION OF SYMBOLS

A . . . base station apparatus, B . . . mobile station apparatus, 27 . .. transmission information control unit, 27 a . . . scheduler unit, 27 b. . . modulation encoding control unit, 27 c . . . frequency schedulerunit, 63 . . . reception quality information control unit, 63 a . . .reception quality information generating unit, 63 b . . . receptionquality measuring unit.

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment

First, a mobile communication system according to a first embodiment ofthe present invention will be described. The mobile communication systemaccording to the present embodiment includes a base station apparatusand a mobile station apparatus and has a configuration similar to thatin FIG. 5(A). FIG. 1 is a functional block diagram showing a schematicconfiguration example of the base station apparatus according to thepresent embodiment. As shown in FIG. 1, a base station apparatus Acomprises a data control unit 1, a modulation encoding unit 3, a mappingunit 5, an inverse fast Fourier transform (IFFT) unit 7, a wirelesstransmitting unit 11, a wireless receiving unit 15, a fast Fouriertransform (FFT) unit 17, a demodulation decoding unit 21, a dataextraction unit 23, a transmission information control unit 27, and anantenna 31. The transmission information control unit 27 includes ascheduler unit 27 a, a modulation and coding control unit 27 b, and afrequency selective scheduler unit 27 c.

In the base station apparatus A, transmission data and control data tobe transmitted to each mobile station apparatus are inputted to the datacontrol unit 1, and the data is sequentially transmitted to the mobilestation apparatuses according to an instruction from the transmissioninformation control unit 27. The modulation encoding unit 3 performs amodulation processing or an error correction coding processing upon asignal outputted from the data control unit based on modulation schemeand coding rate determined by the transmission information control unit27 and outputs the data to the mapping unit. The mapping unit maps thedata outputted from the modulation encoding unit 3 on each sub-carrierbased on frequency selective scheduling information outputted from thetransmission information control unit 27 and outputs the data to theinverse fast Fourier transform unit 7.

The inverse fast Fourier transform unit 7 performs a processing ofinverse fast Fourier transform upon the data outputted from the mappingunit 5, converts the data to a time-series baseband digital signal, andoutputs the signal to the wireless transmitting unit 11. The wirelesstransmitting unit 11 performs digital/analog conversion of the outputsignal from the inverse fast Fourier transform unit 7, up-converts thesignal to a frequency suitable for transmission, and then transmits thesignal to each mobile station apparatus through the antenna.

The scheduler unit 27 a schedules the downlink and the uplink based oncontrol information, such as a resource region that each mobile stationapparatus can use, an intermittent transmission reception cycle, aformat of transmission data channel, and a buffer status. The modulatingand coding control unit 27 b determines the modulation scheme and thecoding rate to be applied to each data based on the reception qualityinformation transmitted from the mobile station apparatus. The frequencyselective scheduler unit 27 c executes a processing of frequencyselective scheduling to be applied to each data based on the receptionquality information transmitted from the mobile station apparatus. Thedata extraction unit 23 separates demodulated and decoded data intoreception data for user and control data, transfers the data to asuperior processing unit, and outputs the reception quality informationto the transmission information control unit 27.

FIG. 2 is a functional block diagram showing a schematic configurationexample of a mobile station apparatus according to the first embodimentof the present invention. As shown in FIG. 2, a mobile station apparatusB comprises a data control unit 41, a modulation encoding unit 43, amapping unit 45, an inverse fast Fourier transform (IFFT) unit 47, awireless transmitting unit 51, a wireless receiving unit 53, a fastFourier transform (FFT) unit 55, a demodulation decoding unit 57, a dataextraction unit 61, a reception quality information control unit 63, andan antenna 65. The reception quality information control unit 63comprises a reception quality information generating unit 63 a and areception quality measuring unit 63 b.

The wireless receiving unit 53, the FFT unit 55, the demodulationdecoding unit 57, the data extraction unit 61, and the reception qualityinformation control unit 63 constitute a receiving unit as a whole, andthe data control unit 41, the modulation encoding unit 43, the mappingunit 45, the inverse fast Fourier transform (IFFT) unit 47, and thewireless transmitting unit 51 constitute a transmitting unit as a whole.

In the mobile station apparatus B shown in FIG. 2, transmission data andcontrol data to be transmitted to the base station apparatus A areinputted to the data control unit 41, and the data is sequentiallytransmitted to the base station apparatus. The modulation encoding unit43 performs a modulation processing or an error correction codingprocessing upon a signal outputted from the data control unit 41 andoutputs the data to the mapping unit 45. The mapping unit 45 maps thedata outputted from the modulation encoding unit 43 on each sub-carrierand outputs the data to the inverse fast Fourier transform unit 47.

The inverse fast Fourier transform unit 47 performs a processing ofinverse fast Fourier transform upon a symbol sequence outputted from themapping unit 45, converts the symbol sequence to a time-series basebanddigital signal, and outputs the signal to the wireless transmitting unit51. The wireless transmitting unit performs digital/analog conversion tothe output signal from the inverse fast Fourier transform unit 47,up-converts the signal to a frequency suitable for transmission, andthen transmits the signal to the base station apparatus A through theantenna.

The reception quality measuring unit 63 b measures the reception qualityof a signal received from the base station apparatus A. The receptionquality information generating unit 63 a generates reception qualityinformation to be transmitted to the base station apparatus A based onthe information measured by the reception quality measuring unit 63 b.

FIG. 3 is a diagram for explaining a communication technique accordingto the first embodiment of the present invention. A diagram on the leftside of FIG. 3 illustrates control signals (L1/L2 grants) transmittedfrom the base station apparatus to the mobile station apparatus,reception quality information, uplink data, and transmission forms ofinformation transmitted in uplink, and a diagram on the right sideillustrates a processing flow corresponding to the slots. In FIG. 3,operations from #slot1 to #slot12 are illustrated as an example.

The mobile station apparatus B transmits data using PUSCH according toresource assignment indicated by a downlink control channel(hereinafter, PDCCH (Physical Downlink Control Channel)) from the basestation apparatus A. Thus, the downlink control channel (PDCCH) is asignal for permitting data transmission in the uplink (uplink datatransmission permission signal, “L1/L2 grant” hereinafter). The L1/L2grant is constituted by, for example, resource assignment information(10 bits), MCS (Modulation and Coding Scheme) (2 bits), transport blocksize (6 bits), HARQ (Hybrid Automatic Repeat Request) redundancy version(2 bits), demodulation pilot signal strength (2 bits), and mobilestation identification information C-RNTI (16 bits).

In the first embodiment of the present invention, the base stationapparatus A includes reception quality information-dedicatedtransmission permission information, which is for permitting the mobilestation apparatus B to transmit only the reception quality informationusing a resource assigned by the L1/L2 grant, in the L1/L2 grantincluding reception quality information transmission permissioninformation which is for permitting the mobile station apparatus B totransmit the reception quality information, and transmits the L1/L2grant. Having received the signal, the mobile station apparatus Btransmits, to the base station apparatus A, only the reception qualityinformation using the resource assigned by the L1/L2 grant(corresponding to #slot4, #slot7, and #slot12 in FIG. 3). The operationsin the slots will be described with reference to FIG. 3.

In #slot2, the base station apparatus A, which has determined toinstruct the mobile station apparatus B to transmit the receptionquality information, transmits the L1/L2 grant in which the permissioninformation (hereinafter, referred to as “reception quality informationtransmission permission information”) is set equal to, for example, “1”,to the mobile station apparatus B (71). Hereinafter, in the embodimentsof the present invention, the reception quality information transmissionpermission information is represented by, for example, 1 bitinformation, and the base station apparatus transmits the L1/L2 grant bysetting “1” when permitting the transmission of the reception qualityinformation, or by setting “0” to avoid transmitting the receptionquality information. In the present embodiment, although such a settingis employed for simplifying the description, it is obvious that othersetting methods can be used. Having received the L1/L2 grant in whichthe reception quality information transmission permission information isset equal to “1”, the mobile station apparatus B simultaneouslytransmits, to the base station apparatus A, the reception qualityinformation and the uplink data using the resource assigned by the L1/L2grant (72).

In #slot3, the base station apparatus A transmits a normal L1/L2 grantto the mobile station apparatus B (73), and the mobile station apparatusB that has received the signal transmits, to the base station apparatusA, the uplink data using the resource assigned by the L1/L2 grant (74).

Next, an operation of #slot 4 will be described.

In #slot4, the base station apparatus A, having determined to permit themobile station apparatus B to transmit only the reception qualityinformation, transmits the L1/L2 grant in which the designationinformation (hereinafter, referred to as “reception qualityinformation-dedicated transmission permission information”) is set equalto, for example, “1”, to the mobile station apparatus B (75).Hereinafter, in the embodiments of the present invention, the receptionquality information-dedicated transmission permission signal isrepresented by, for example, 1 bit information, and the base stationapparatus transmits the L1/L2 grant by setting “1” when permitting thetransmission of only the reception quality information, or by setting“0” to avoid transmitting only the reception quality information. In thepresent embodiment, although such a setting is employed for simplifyingthe description, it is obvious that other setting methods can be used.Having received the L1/L2 grant in which the reception qualityinformation-dedicated transmission permission information is set equalto “1”, the mobile station apparatus B transmits, to the base stationapparatus A, only the reception quality information using the assignedresource (76). However, the mobile station apparatus B transmits thereception quality information and ACK/NACK in case that the ACK/NACK ofHARQ for the downlink data needs to be transmitted.

The L1/L2 grants transmitted from the base station apparatus in #slot2,#slot3, and #slot4 in the first embodiment will be further described. Inthe L1/L2 grants transmitted in #slot2, #slot3, and #slot4, thereception quality information transmission permission information andthe reception quality information-dedicated transmission permissioninformation are always included. Thus, the L1/L2 grants always include 2bit information. In the 2 bit information, the base station apparatussets the reception quality information transmission permissioninformation equal to “1” and the reception quality information-dedicatedtransmission permission information equal to “0” in #slot2 and sets thereception quality information transmission permission information equalto “0” and the reception quality information-dedicated transmissionpermission information equal to “0” in #slot3. The base stationapparatus sets the reception quality information transmission permissioninformation equal to “1” and the reception quality information-dedicatedtransmission permission information equal to “1” in #slot4. In theexplanation of slot2, #slot3, and #slot4 described above, although onlyinformation set equal to “1” is described for simplifying theexplanation, the L1/L2 grants always include 2 bit information of thereception quality information transmission permission information andthe reception quality information-dedicated transmission permissioninformation in the first embodiment. Hereinafter, in the explanation ofthe embodiments of the present invention, only information set equal to“1” will be basically described for simplifying the explanation.

FIG. 3 similarly illustrates that the base station apparatus A transmitsthe L1/L2 grants in which the reception quality information transmissionpermission information is set equal to “1” in #slot6, #slot9, and#slot10, and that the mobile station apparatus B that has received thesignals simultaneously transmits, to the base station apparatus A, thereception quality information and the uplink data using the assignedresources (78, 82, and 84). FIG. 3 also illustrates that the basestation apparatus transmits a normal L1/L2 grant in #slot11, and thatthe mobile station apparatus B that has received the signal transmits,to the base station apparatus A, the uplink data using the assignedresource (86). FIG. 3 further illustrates that the base stationapparatus transmits L1/L2 grants in which the reception qualityinformation-dedicated transmission permission information is set equalto “1” to the mobile station apparatus B in #slot7 and #slot12, and themobile station apparatus that has received the signals transmits, to thebase station apparatus A, only the reception quality information (80 and88). In #slot7 and #slot12, only the reception quality information istransmitted to the base station apparatus A even if there is uplink datain the information transmitted by the mobile station apparatus B usingthe uplink.

In FIG. 3, numerals 105 to 140 indicate the existence of data in theslots. The illustration of the L1/L2 grants depicted with horizontalhatches for #slot2, #slot6, #slot9, and #slot10 indicates that the basestation apparatus A transmits L1/L2 grants in which the receptionquality information transmission permission information is set equal to“1” and the reception quality information-dedicated transmissionpermission information is set equal to “0”. The illustration of theL1/L2 grants depicted in black for #slot4, #slot7, and #slot12 indicatesthat the base station apparatus A transmits L1/L2 grants in which thereception quality information transmission permission information is setequal to “1” and the reception quality information-dedicatedtransmission permission information is set equal to “1”.

The illustration of the transmission forms depicted with diagonal lines(equivalent to reception quality information) and white frames(equivalent to uplink data) for #slot2, #slot6, #slot9, and #slot10indicates that the mobile station apparatus B simultaneously transmits,to the base station apparatus A, the reception quality information andthe uplink data. The illustration of the transmission forms depicted inlattice pattern for #slot4, #slot7, and #slot12 indicates that themobile station apparatus B transmits, to the base station apparatus A,only the reception quality information.

The processing flow corresponding to the slots will be described withreference to the diagram on the right side of FIG. 3.

In #slot2, the base station apparatus A transmits an L1/L2 grant inwhich the reception quality information transmission permissioninformation is set equal to “1” (71). Receiving the signal, the mobilestation apparatus B simultaneously transmits the reception qualityinformation and the uplink data using the assigned resource (72). Thesame processing is executed in #slot6, #slot9, and #slot 10.

In #slot3, the base station apparatus A transmits a normal L1/L2 grant(73). Receiving the signal, the mobile station apparatus B transmits theuplink data using the assigned resource (74). The same processing isexecuted in #slot11.

In #slot4, the base station apparatus A transmits an L1/L2 grant inwhich the reception quality information-dedicated transmissionpermission information is set equal to “1” (75). Receiving the signal,the mobile station apparatus B transmits, to the base station apparatus,only the reception quality information using the assigned resource (76).In #slot7 and #slot12, only the reception quality information istransmitted to the base station apparatus A even if there is uplink datain the information transmitted by the mobile station apparatus B usingthe uplink.

The reception quality information-dedicated transmission permissioninformation included in the L1/L2 grant can be represented by otherinformation included in the L1/L2 grant without adding a new informationbit. For example, all values of HARQ redundancy versions for the uplinkdata included in the L1/L2 grants can be set equal to 0, all values ofMCS for the uplink data can be set equal to 0, or the transport blocksize for the uplink data can be set equal to 0 to represent thereception quality information-dedicated transmission permissioninformation. The fact that these values are set equal to 0 denotes thatthe L1/L2 grants from the base station apparatus indicate that there isno need to transmit anything in the uplink data transmitted from themobile station apparatus. The mobile station apparatus that has receivedthe signal recognizes that the L1/L2 grant from the base stationapparatus is not a normal L1/L2 grant and transmits only the receptionquality information to the base station apparatus.

Thus, in #slot4, #slot7, and #slot12 of FIG. 3, the L1/L2 grants inwhich all values of the HARQ redundancy versions for the uplink data areset equal to 0, all values of MCS for the uplink data are set equal to0, or the transport block size for the uplink data is set equal to 0, istransmitted from the base station apparatus A, and the mobile stationapparatus B that has received the signal transmits, to the base stationapparatus A, only the reception quality information using the resourcesassigned by the L1/L2 grants. In that case, the reception qualityinformation transmission permission information is set equal to “1”.Which information included in the L1/L2 grants transmitted from the basestation apparatus A will be used, and with what way of setting in theinformation the mobile station apparatus B will transmit only thereception quality information are determined in advance inspecifications or the like, and this is known information between thebase station apparatus A and the mobile station apparatus B. In thisway, there is no need to add a new information bit to the L1/L2 grant asthe reception quality information-dedicated transmission permissioninformation as a result of using other information included in the L1/L2grant to represent the reception quality information-dedicatedtransmission permission information, and the mobile station apparatus Bcan transmit only the reception quality information to the base stationapparatus A without increasing the amount of information included in theL1/L2 grant.

As described, according to the first embodiment of the presentinvention, the base station apparatus transmits an L1/L2 grant includingreception quality information-dedicated transmission permissioninformation that permits transmission of only the reception qualityinformation, and the mobile station apparatus that has received thesignal transmits only the reception quality information to the basestation apparatus. As a result, the mobile station apparatus cantransmit only the reception quality information.

The mobile station apparatus can transmit reception quality informationincluding a large amount of information because the resource assigned bythe L1/L2 grant including the reception quality information-dedicatedtransmission permission information from the base station apparatus isused to transmit the reception quality information. As a result, forexample, the mobile station apparatus can transmit the reception qualityinformation including a large amount of information even in a service inwhich a great amount of data (UDP packets), such as moving images, iscontinuously downloaded without uplink data.

Furthermore, since the reception quality information-dedicatedtransmission permission information, which permits the mobile stationapparatus to transmit only the reception quality information, isincluded in the L1/L2 grant and transmitted to the mobile stationapparatus, the base station apparatus can control how often the mobilestation apparatus transmits only the reception quality information.

This allows transmission control flexibly responding to the amount ofinformation and the frequency of transmissions of the reception qualityinformation transmitted from the mobile station apparatus, and moreefficient communication control (scheduling) between the base stationapparatus and the mobile station apparatus can be achieved.

Second Embodiment

FIG. 4 is a diagram for explaining a communication technique accordingto a second embodiment of the present invention. A diagram on the leftside of FIG. 4 illustrates control signals (L1/L2 grants) transmittedfrom the base station apparatus to the mobile station apparatus,reception quality information, uplink data, and transmission forms ofinformation transmitted in uplink, and a diagram on the right sideillustrates a processing flow corresponding to the slots. In FIG. 4,operations from #slot1 to #slot12 are illustrated as an example.

In the second embodiment of the present invention, the base stationapparatus transmits RRC signaling including reception qualityinformation transmission instruction information to the mobile stationapparatus. The base station apparatus also transmits an L1/L2 grantincluding reception quality information transmission permissioninformation which permits the mobile station apparatus to transmit, thereception quality information, to the mobile station apparatus. Thereception quality information transmission instruction informationherein is, as described below, information for designating to use thereception quality information transmission permission information(information for designating to transmit the reception qualityinformation) as the reception quality information-dedicated transmissionpermission information (information for designating to transmit only thereception quality information). Numerals 161 to 199 have similar meaningas in FIG. 3.

The operations in the slots will be described with reference to FIG. 4.

Prior to #slot1, it is designated in the reception quality informationtransmission instruction information in the RRC signaling from the basestation apparatus A that the mobile station apparatus B should transmitthe reception quality information to the base station apparatus wheneveran L1/L2 grant in which the reception quality information transmissionpermission information is set equal to “1” is received.

As described also in the first embodiment, the base station apparatus A,which has determined in #slot2 to instruct the mobile station apparatusB to transmit the reception quality information, transmits an L1/L2grant in which the reception quality information transmission permissioninformation is set equal to “1”, to the mobile station apparatus B(141). Having received the L1/L2 grant including the reception qualityinformation transmission permission information, the mobile stationapparatus B simultaneously transmits, to the base station apparatus A,the reception quality information and the uplink data using the resourceassigned by the L1/L2 grant (142). In #slot3, the base station apparatusA transmits a normal L1/L2 grant to the mobile station apparatus B(143), and the mobile station apparatus B that has received the signaltransmits, to the base station apparatus A, the uplink data using theresource assigned by the L1/L2 grant (144).

FIG. 4 similarly illustrates that the base station apparatus A transmitsL1/L2 grants in which the reception quality information transmissionpermission information is set equal to “1”, in #slot4 and #slot6, andthe mobile station apparatus B that has received the signalsimultaneously transmits, to the base station apparatus, the uplink dataand the reception quality information using the assigned resources (146and 148).

Next, an operation of #slot8 will be described.

In #slot8, the base station apparatus A designates the mobile stationapparatus B to use the reception quality information transmissionpermission information as the reception quality information-dedicatedtransmission permission information, by the RRC signaling including thereception quality information transmission instruction information(149).

The reception quality information transmission instruction informationwill be described here. In the present second embodiment, the mobilestation apparatus B that has received the RRC signaling including thereception quality information transmission instruction informationinterprets the reception quality information transmission permissioninformation included in the L1/L2 grant transmitted from the basestation apparatus A as the reception quality information-dedicatedtransmission permission information. For example, if the base stationapparatus A represent the reception quality information transmissionpermission information by an information bit “A”, informationrepresented by the same information bit “A” serves as the receptionquality information-dedicated transmission permission information afterthe RRC signaling including the reception quality informationtransmission instruction information is received.

This point will be described using FIG. 4.

In FIG. 4, it is assumed that the base station apparatus sets theinformation bit “A”, which represents the reception quality informationtransmission permission information, equal to “1” in #slot2, #slot4, and#slot6 to permit the mobile station apparatus to transmit the receptionquality information. Having received the signal, the mobile stationapparatus B simultaneously transmits the reception quality informationand the uplink data. The base station apparatus A transmits the RRCsignaling including the reception quality information transmissioninstruction information in #slot8 (149). The base station apparatus Acan further set the same information bit “A”, which represents thereception quality information transmission permission information, equalto “1” in #slot9, #slot10, and #slot12 to permit the mobile stationapparatus B to transmit only the reception quality information. Thus,the reception quality information transmission permission informationand the reception quality information-dedicated transmission permissioninformation represented as 2 bit information in the first embodiment canbe combined into the same one information (information bit “A”) bytransmitting the RRC signaling. It can also be stated that the receptionquality information transmission instruction information included in theRRC signaling from the base station apparatus A is information forswitching the interpretation from the reception quality informationtransmission permission information to the reception qualityinformation-dedicated transmission permission information.

In #slot9 of FIG. 4, the base station apparatus A transmits an L1/L2grant in which the reception quality information transmission permissioninformation is set equal to “1”, and the mobile station apparatus B thathas received the signal transmits, to the base station apparatus A, onlythe reception quality information although there is uplink data in theinformation transmitted using the uplink (153). Thus, in the slot afterthe RRC signaling including the reception quality informationtransmission instruction information is transmitted, the mobile stationapparatus B that has received the L1/L2 grant in which the receptionquality information transmission permission information is set equal to“1” does not transmit the uplink data to the base station apparatus Aeven if there is uplink data in the information transmitted using theuplink. In FIG. 4, the mobile station apparatus B that has received theL1/L2 grant in which the reception quality information transmissionpermission information is set equal to “1”, similarly transmits only thereception quality information to the base station apparatus in #slot12(157).

The #slot10 illustrates that the base station apparatus A transmits theL1/L2 grant in which the reception quality information transmissionpermission information is set equal to “1”, to the mobile stationapparatus B (152), and that the mobile station apparatus B that hasreceived the signal transmits, to the base station apparatus A, only thereception quality information using the resource assigned by the L1/L2grant (153).

In #slot11, the base station apparatus A transmits a normal L1/L2 grantto the mobile station apparatus B (154), and the mobile stationapparatus B that has received the signal transmits, to the base stationapparatus A, the uplink data using the resource assigned by the L1/L2grant (155).

Next, a processing flow corresponding to the slots will be described.

In #slot2, the base station apparatus A transmits an L1/L2 grant inwhich the reception quality information transmission permissioninformation is set equal to “1” (141). Having received the signal, themobile station apparatus B simultaneously transmits the receptionquality information and the uplink data using the assigned resource(142). The same processing is executed in #slot4 and #slot6.

In #slot3, the base station apparatus transmits a normal L1/L2 grant(143). Having received the signal, the mobile station apparatus Btransmits the uplink data using the assigned resource (144). The sameprocessing is executed in #slot11.

In #slot8, the base station apparatus A transmits RRC signalingincluding reception quality information transmission designationinformation (149) to designate that the reception quality informationtransmission permission information be used as the reception qualityinformation-dedicated transmission permission information. Havingreceived the signal, the mobile station apparatus B determines thereception quality information transmission permission information as thereception quality information-dedicated transmission permissioninformation in the subsequent slots (switches the interpretation).

In #slot9, the base station apparatus A transmits an L1/L2 grant inwhich the reception quality information transmission permissioninformation is set equal to “1” (150). Having received the signal, themobile station apparatus B transmits, to the base station apparatus A,only the reception quality information using the assigned resourcealthough there is uplink data in the information to be transmitted usingthe uplink (151). The same processing is executed in #slot 12.

In #slot10, the base station apparatus A transmits an L1/L2 grant inwhich the reception quality information-dedicated transmissionpermission information is set equal to “1” (152). Having received thesignal, the mobile station apparatus B transmits, to the base stationapparatus A, only the reception quality information using the assignedresource (153).

As described, according to the second embodiment of the presentinvention, the base station apparatus transmits the RRC signalingincluding the reception quality information transmission designationinformation and designates the mobile station apparatus that hasreceived the signal to use the reception quality informationtransmission permission information as the reception qualityinformation-dedicated transmission permission information. As a result,the mobile station apparatus B can transmit only the reception qualityinformation to the base station apparatus A without increasing theamount of information included in the L1/L2 grant.

The mobile station apparatus can transmit the reception qualityinformation including a large amount of information since the resourceassigned by the L1/L2 grant including the reception quality informationtransmission permission information from the base station apparatus isused to transmit the reception quality information. As a result, forexample, the mobile station apparatus can transmit the reception qualityinformation including a large amount of information even in a service inwhich a great amount of data (UDP packets), such as moving images, iscontinuously downloaded without uplink data.

Furthermore, since the reception quality information transmissionpermission information that permits the mobile station apparatus totransmit the reception quality information is included in the L1/L2grant and transmitted to the mobile station apparatus, the base stationapparatus can control how often the mobile station apparatus transmitsthe reception quality information.

This allows transmission control flexibly responding to the amount ofinformation and the frequency of transmissions of the reception qualityinformation transmitted from the mobile station apparatus, and moreefficient communication control (scheduling) between the base stationapparatus and the mobile station apparatus can be achieved.

The RRC signaling including the reception quality informationtransmission instruction information from the base station apparatus inthe second embodiment of the present invention is transmitted when, forexample, the service performed between the mobile station apparatus andthe base station apparatus switches from a normal service in whichuplink data exists, to a service in which a great amount of data (UDPpackets), such as moving images, is continuously downloaded without agreat volume of uplink data.

All embodiments of the present invention can also be applied to thetransmit diversity such as SDM (Space Division Multiplexing) using MIMOcommunication (Multiple Input Multiple Output), SFBC (Space-FrequencyBlock Diversity), and CDD (Cyclic Delay Diversity). The receptionquality information in the present embodiment includes the number ofstreams that the mobile station apparatus can receive in the MIMOcommunication (RANK information) and index information indicatinginformation of preprocessing (Pre-coding) performed in advance tocorrectly separate a plurality of streams transmitted from the basestation apparatus (PMI (Pre-coding Matrix Index) information).

Although the embodiments of the present invention have been described indetail with reference to the drawings, the specific configurations arenot limited to the embodiments, and designs and the like that do notdepart from the scope of the invention are also included in the claims.

INDUSTRIAL APPLICABILITY

The present invention is applicable to a communication apparatus.

1-26. (canceled)
 27. A mobile communication system in which a mobilestation apparatus transmits reception quality information to a basestation apparatus, the reception quality information indicating qualityof a signal received from the base station apparatus, characterized inthat the base station apparatus transmits, to the mobile stationapparatus, an uplink data transmission permission signal includinginformation for instructing transmission of reception qualityinformation without uplink data, and the mobile station apparatustransmits, to the base station apparatus, reception quality informationwithout uplink data in case that the information for instructingtransmission of reception quality information without uplink data isincluded in the uplink data transmission permission signal.
 28. Themobile communication system according to claim 27, characterized in thatthe mobile station apparatus transmits, to the base station apparatus,the reception quality information using a physical uplink sharedchannel.
 29. A mobile communication system in which a mobile stationapparatus transmits reception quality information to a base stationapparatus using a physical uplink shared channel, the reception qualityinformation indicating quality of a signal received from the basestation apparatus, characterized in that the base station apparatustransmits, to the mobile station apparatus, an uplink data transmissionpermission signal including information for instructing transmission ofreception quality information without uplink data, and the mobilestation apparatus transmits, to the base station apparatus, receptionquality information without uplink data in case that the information forinstructing transmission of reception quality information without uplinkdata is included in the uplink data transmission permission signal. 30.A mobile communication system in which a mobile station apparatustransmits uplink data to a base station apparatus using a physicaluplink shared channel assigned by an uplink data transmission permissionsignal, characterized in that the base station apparatus transmits, tothe mobile station apparatus, the uplink data transmission permissionsignal including information for instructing transmission of receptionquality information without uplink data, and the mobile stationapparatus transmits reception, to the base station apparatus, qualityinformation without uplink data using the physical uplink shared channelin case that the information for instructing transmission of receptionquality information without uplink data is included in the uplink datatransmission permission signal.
 31. A base station apparatus in a mobilecommunication system in which a mobile station apparatus transmitsreception quality information to the base station apparatus, thereception quality information indicating quality of a signal receivedfrom the base station apparatus, the base station apparatuscharacterized by comprising: an unit for transmitting an uplink datatransmission permission signal including information for instructingtransmission of reception quality information without uplink data to themobile station apparatus.
 32. A base station apparatus in a mobilecommunication system in which a mobile station apparatus transmitsreception quality information to the base station apparatus using aphysical uplink shared channel, the reception quality informationindicating quality of a signal received from the base station apparatus,the base station apparatus characterized by comprising: an unit fortransmitting an uplink data transmission permission signal includinginformation for instructing transmission of reception qualityinformation without uplink data to the mobile station apparatus.
 33. Abase station apparatus in a mobile communication system in which amobile station apparatus transmits uplink data to a base stationapparatus using a physical uplink shared channel assigned by an uplinkdata transmission permission signal, the base station apparatuscharacterized by comprising: an unit for transmitting the uplink datatransmission permission signal including information for instructingtransmission of reception quality information without uplink data to themobile station apparatus.
 34. A mobile station apparatus in a mobilecommunication system in which the mobile station apparatus transmitsreception quality information to a base station apparatus, the receptionquality information indicating quality of a signal received from thebase station apparatus, the mobile station apparatus characterized bycomprising: an unit for receiving an uplink data transmission permissionsignal from the base station apparatus; and an unit for transmittingreception quality information without uplink data to the base stationapparatus in case that information for instructing transmission ofreception quality information without uplink data is included in theuplink data transmission permission signal.
 35. The mobile stationapparatus according to claim 34, characterized in that the unit fortransmitting the reception quality information to the base stationapparatus transmits, to the base station apparatus, the receptionquality information using a physical uplink shared channel.
 36. A mobilestation apparatus in a mobile communication system in which the mobilestation apparatus transmits reception quality information to a basestation apparatus using a physical uplink shared channel, the receptionquality information indicating quality of a signal received from thebase station apparatus, the mobile station apparatus characterized bycomprising: an unit for receiving an uplink data transmission permissionsignal from the base station apparatus; and an unit for transmittingreception quality information without uplink data to the base stationapparatus in case that information for instructing transmission ofreception quality information without uplink data is included in theuplink data transmission permission signal.
 37. A mobile stationapparatus in a mobile communication system in which the mobile stationapparatus transmits uplink data to a base station apparatus using aphysical uplink shared channel assigned by an uplink data transmissionpermission signal, the mobile station apparatus characterized bycomprising: an unit for receiving the uplink data transmissionpermission signal from the base station apparatus; and an unit fortransmitting reception quality information without uplink data using thephysical uplink shared channel to the base station apparatus in casethat information for instructing transmission of reception qualityinformation without uplink data is included in the uplink datatransmission permission signal.
 38. A communication method of a basestation apparatus in a mobile communication system in which a mobilestation apparatus transmits uplink data to the base station apparatususing a physical uplink shared channel assigned by an uplink datatransmission permission signal, the communication method characterizedby comprising: transmitting the uplink data transmission permissionsignal including information for instructing transmission of receptionquality information without uplink data to the mobile station apparatus.39. A communication method of a mobile station apparatus in a mobilecommunication system in which the mobile station apparatus transmitsuplink data to a base station apparatus using a physical uplink sharedchannel assigned by an uplink data transmission permission signal, thecommunication method characterized by comprising: receiving the uplinkdata transmission permission signal from the base station apparatus;transmitting reception quality information without uplink data using thephysical uplink shared channel to the base station apparatus in casethat information for instructing transmission of reception qualityinformation without uplink data is included in the uplink datatransmission permission signal.